Lip and oral cavity cancer is a disease that starts in lips or mouth.

The oral cavity refers to the mouth. It includes:

• the front two thirds of the tongue
• the gingiva (gums)
• the buccal mucosa (the lining of the inside of the cheeks)
• the floor (bottom) of the mouth under the tongue
• the hard palate (the roof of the mouth)
• the retromolar trigone (the small area behind the wisdom teeth)

Most lip and oral cavity cancers start in squamous cells, the thin, flat cells lining the inside of the lips and oral cavity. Cancers that start in squamous cells are called squamous cell carcinomas. Cancer cells may spread into deeper tissue as the cancer grows. Squamous cell carcinoma usually develops in areas of leukoplakia (white patches of cells that do not rub off).

Lip and oral cavity cancer is a type of head and neck cancer.

Tobacco and alcohol use can affect the risk of lip and oral cavity cancer.

Lip and oral cavity cancer is caused by certain changes to the way lip and oral cavity cells function, especially how they grow and divide into new cells. There are many risk factors for lip and oral cavity cancer, but many do not directly cause cancer. Instead, they increase the chance of DNA damage in cells that may lead to lip and oral cavity cancer. Learn more about how cancer develops at What Is Cancer?

A risk factor is anything that increases the chance of getting a disease. Some risk factors for lip and oral cavity cancer, such as tobacco and alcohol use, can be changed. However, risk factors also include things people cannot change, like their genetics. Learning about risk factors for lip and oral cavity cancer can help you make changes that might lower your risk of getting it.

Risk factors for lip and oral cavity cancer include:

• using tobacco products
• heavy alcohol use
• being exposed to natural sunlight or artificial sunlight (such as from tanning beds) over long periods of time
• being male

Learn more about Tobacco, including help with quitting.

Having one or more of these risk factors does not mean that you will get lip and oral cavity cancer. Many people with risk factors never develop lip and oral cavity cancer, while others with no known risk factors do. Talk with your doctor if you think you may be at risk.

Signs of lip and oral cavity cancer include a sore or lump on the lips or in the mouth.

These and other signs and symptoms may be caused by lip and oral cavity cancer or by other conditions. Check with your doctor if you have any of the following:

• a sore on the lip or in the mouth that does not heal
• a lump or thickening on the lips or gums or in the mouth
• a white or red patch on the gums, tongue, or lining of the mouth
• bleeding, pain, or numbness in the lip or mouth
• change in voice
• loose teeth or dentures that no longer fit well
• trouble chewing or swallowing or moving the tongue or jaw
• swelling of jaw
• sore throat or feeling that something is caught in the throat

Lip and oral cavity cancer may not have any symptoms and is sometimes found during a regular dental exam.

Tests that examine the mouth and throat are used to diagnose and stage lip and oral cavity cancer.

If you have symptoms that suggest lip and oral cavity cancer, your doctor will need to find out if these are due to cancer or another problem. They will ask when the symptoms started and how often you have been having them. They will also ask about your personal and family health history and do a physical exam. Based on these results, the doctor may recommend other tests. If you are diagnosed with lip and oral cavity cancer, the results of these tests will help you and your doctor plan treatment.

The following tests and procedures are used to diagnose and stage lip and oral cavity cancer:

• Physical exam of the lips and oral cavity is an exam to check the lips and oral cavity for abnormal areas. The medical doctor or dentist will feel the entire inside of the mouth with a gloved finger and examine the oral cavity with a small long-handled mirror and lights. This will include checking the insides of the cheeks and lips; the gums; the roof and floor of the mouth; and the top, bottom, and sides of the tongue. The neck will be felt for swollen lymph nodes. A history of the patient’s health habits and past illnesses and medical and dental treatments will also be taken.
• Endoscopy is a procedure to look at organs and tissues inside the body to check for abnormal areas. An endoscope is inserted through an incision (cut) in the skin or opening in the body, such as the mouth. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue or lymph node samples, which are checked under a microscope for signs of disease.
• Biopsy is the removal of cells or tissues so they can be viewed under a microscope by a pathologist. If leukoplakia is found, cells taken from the patches are also checked under the microscope for signs of cancer.
• Exfoliative cytology is a procedure to collect cells from the lip or oral cavity. A piece of cotton, a brush, or a small wooden stick is used to gently scrape cells from the lips, tongue, mouth, or throat. The cells are viewed under a microscope to find out if they are abnormal.
• MRI (magnetic resonance imaging) uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• CT scan (CAT scan) uses a computer linked to an x-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create 3-D views of tissues and organs. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• Barium swallow is a series of x-rays of the esophagus and stomach. The patient drinks a liquid that contains barium (a silver-white metallic compound). The liquid coats the esophagus and x-rays are taken. This procedure is also called an upper GI series.
• PET scan (positron emission tomography scan) uses a small amount of radioactive sugar (also called glucose) that is injected into a vein. Then a scanner rotates around the body to make detailed, computerized pictures of areas inside the body where the glucose is taken up. Because cancer cells often take up more glucose than normal cells, the pictures can be used to find cancer cells in the body.
• Bone scan is a procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones with cancer and is detected by a scanner.

Some people decide to get a second opinion.

You may want to get a second opinion to confirm your cancer diagnosis and treatment plan. If you seek a second opinion, you will need to get medical test results and reports from the first doctor to share with the second doctor. The second doctor will review the pathology report, slides, and scans. They may agree with the first doctor, suggest changes or another treatment approach, or provide more information about your cancer.

To learn more about choosing a doctor and getting a second opinion, see Finding Cancer Care. You can contact NCI’s Cancer Information Service via chat, email, or phone (both in English and Spanish) for help finding a doctor, hospital, or getting a second opinion. For questions you might want to ask at your appointments, see Questions to Ask Your Doctor About Cancer.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis depends on:

• the cancer stage
• where the tumor is in the lip or oral cavity
• whether the cancer has spread to blood vessels

For patients who smoke, the chance of recovery is better if they stop smoking before beginning radiation therapy.

Treatment options depend on:

• the stage of the cancer
• the size of the tumor and where it is in the lip or oral cavity
• whether the patient's appearance and ability to talk and eat can stay the same
• the patient's age and general health

Patients who have had lip and oral cavity cancer have an increased risk of developing a second cancer in the head or neck. Frequent and careful follow-up is important. Clinical trials are studying the use of retinoid drugs to reduce the risk of a second head and neck cancer. Information about ongoing clinical trials is available from the NCI website.